/Engine/Plugins/Runtime/NetworkPrediction/Source/NetworkPrediction/Public/NetworkPredictionReplicationProxy.h
FServerRPCProxyParameter Used for the client->Server RPC. Since this is instantiated on the stack by the replication system prior to net serializing, we have no opportunity to point the RPC parameter to the member variables we want. So we serialize into a generic temp byte buffer and move them into the real buffers on the component in the RPC body (via ::NetSerialzeToProxy).
[USTRUCT](Programming/UnrealArchitecture/Reference/Structs)() struct FServerReplicationRPCParameter